This kind of object area detection device and the like are used for distinctively detecting an object overlying a stationary object. Related art thereof will be described below.
A first example of the related art is disclosed in Patent Document 1. A mobile object recognition method disclosed in Patent Document 1 uses a template image of a preregistered target object or a template image of a target object acquired based on an aspect that an appearing position or an appearing time of the object is noted by a method, to thereby follow the object by means of pattern matching. Thereby, even if the object overlies, the overlying object is distinguished by detecting the position of the object.
A second example of the related art is disclosed in Patent Document 2. A road object monitoring device disclosed in Patent Document 2 uses a reference image not including an object as a background image, and generates a background differential image from a difference between the background image and an input image (time t) (background difference method). The device also generates continuous differential images from a difference between an input image at time t and an input image at time (t−1). The device binarizes both differential images, detects a mobile object from their logical AND, and detects a stationary object from exclusive OR, to thereby distinguish an overlying object.    Patent Document 1: Japan Unexamined Patent Publication 6-030417 (FIG. 20, etc)    Patent Document 2: Japan Unexamined Patent Publication 6-180749 (FIG. 1, etc)